Apparatus and Method for Training Device-To-Device Physical Interface

1. A method of training a physical interface between a first device and a second device, the method comprising: determining a timing of a signal transmission in a first candidate group, from a plurality of lanes between the first device and the second device, by performing a first training of the physical interface, the first training including temporarily setting the first candidate group and communicating a signal between the first device and the second device using the first candidate group of lanes from among the plurality of lanes; determining a timing of a signal transmission in a second candidate group, from the plurality of lanes between the first device and the second device, by performing a second training of the physical interface, the second training including temporarily setting the second candidate group and communicating a signal between the first device and the second device using the second candidate group of lanes from among the plurality of lanes, the second candidate group being different from the first candidate group; determining a lane group based on a comparison of the timings determined during the first training and the second training; and setting the second device so that the determined lane group is used for the physical interface, wherein the physical interface includes a high bandwidth memory (HBM) interface and the second device includes a plurality of memory dies that are stacked.

2. The method of claim 1, further comprising: selecting the second candidate group among the plurality of lanes based on a result of the first training.

3. The method of claim 2, wherein the performing of the first training comprises: detecting a plurality of first valid window margins, each valid window margin in the plurality of first valid window margins corresponding to a lane from among the lanes in the first candidate group, and wherein the selecting of the second candidate group comprises: identifying a first lane corresponding to a minimum first valid window margin of the plurality of first valid window margins; and selecting lanes from among the plurality of lanes excluding the first lane as the second candidate group.

4. The method of claim 3, wherein the performing of the second training comprises: detecting a plurality of second valid window margins, each valid window margin in the plurality of second valid window margins corresponding to a lane from among the lanes in the second candidate group, and wherein the determining of the lane group comprises: identifying a second lane corresponding to a minimum second valid window margin of the plurality of second valid window margins; identifying a higher valid window margin among the minimum first valid window margin and the minimum second valid window margin; and selecting a candidate group corresponding to the identified valid window margin among the first candidate group and the second candidate group, as the determined lane group.

5. The method of claim 2, wherein the selecting of the second candidate group comprises: identifying deactivation of at least one function of the physical interface; and selecting the second candidate group such that the second candidate group includes at least one lane that is unused as a result of the at least one function being in a deactivated state.

6. The method of claim 5, wherein the at least one function comprises: at least one of a data masking function, a data bus inversion function, and an error correction function.

7. The method of claim 1, further comprising: performing a third training by communicating with the second device by using a third candidate group of lanes from among the plurality of lanes, the third candidate group being different from the first candidate group and different from the second candidate group, wherein the determined lane group is determined based on a result of the first training, a result of the second training, and a result of the third training.

8. The method of claim 1, further comprising: verifying lanes between the first device and the second device from among the plurality of lanes, wherein the first candidate group and the second candidate group include lanes, from among the plurality of lanes, that are determined to be valid lanes as a result of the verifying.

9. The method of claim 1, wherein the performing of the first training includes transmitting a first soft mapping command for the temporarily setting the first candidate group to the second device, wherein the performing of the second training includes transmitting a second soft mapping command for the temporarily setting the second candidate group to the second device, and wherein the setting of the second device includes transmitting to the second device a hard mapping command permanently setting the lane group.

10. A first device configured to communicate with a second device based on a physical interface, the first device comprising: a routing circuit configured to select some of a plurality of lanes based on a control signal, for the physical interface; and processing circuitry configured to, generate the control signal for determining timings for different candidate groups of the plurality of lanes by training the physical interface by using each of different candidate groups of lanes from among the plurality of lanes to communicate a signal between the first device and the second device, and determine a lane group to be used for the physical interface based on a result of the training, the result of the training including a comparison of the timings for the different candidate groups, wherein the processing circuitry is further configured to identify deactivation of at least one function of the physical interface, and generate the control signal for training the physical interface based on a candidate group of lanes, from among the plurality of lanes, that includes at least one lane that is unused as a result of the at least one function being in a deactivated state.

11. The first device of claim 10, wherein the processing circuitry is further configured to perform a first training of the physical interface by using a first candidate group among the plurality of lanes, select a second candidate group among the plurality of lanes based on a result of the first training, and perform a second training of the physical interface by using the second candidate group.

12. The first device of claim 11, wherein the processing circuitry is further configured to detect a plurality of first valid window margins each corresponding to a plurality of lanes comprised in the first candidate group in the first training, identify a first lane corresponding to a minimum first valid window margin of the plurality of first valid window margins, and select the second candidate group from the plurality of lanes excluding the first lane.

13. The first device of claim 10, wherein the routing circuit comprises: a decoder configured to generate a plurality of select signals by decoding the control signal; and a plurality of multiplexers configured to form paths based on the plurality of select signals.

14. A system comprising: a plurality of interconnections; and a first device and a second device configured to communicate with each other via at least some of the plurality of interconnections based on a physical interface, wherein the first device and the second device are further configured to train the physical interface by using each of a plurality of different candidate groups, each candidate group including interconnections from among the plurality of interconnections, to communicate a signal between the first device and the second device, wherein the physical interface includes a high bandwidth memory (HBM) interface, wherein the second device includes a plurality of memory dies that are stacked, wherein the plurality of interconnections include at least one through silicon via penetrating at least one of the plurality of memory dies, and wherein first device is configured to determine an interconnection group to be used for the physical interface based on training results, the training results including a comparison of timings for each of the plurality of different candidate groups.

15. The system of claim 14, wherein the first device and the second device are further configured to perform a first training of the physical interface by using a first candidate group from among the plurality of different candidate groups, and perform a second training of the physical interface by using a second candidate group from among the plurality of different candidate groups, and wherein the first device is configured to select the second candidate group among the plurality of interconnections based on a result of the first training.

16. The system of claim 14, wherein the first device and the second device are further configured to train the physical interface using a candidate group, from among the plurality of different candidate groups, that includes at least one interconnection, from among the plurality of interconnections, that is unused as a result of at least one function of the physical interface being set in a deactivated state.

17. The system of claim 14, wherein the first device includes a base die, and wherein the plurality of memory dies are stacked on the base die.